P114-09 Unveiling Hidden MET-Mediated Primary Alectinib Resistance in ALK-Positive Non-Small Cell Lung Cancer

More recently, alectinib has superseded crizotinib, an ALK/ROS1/MET inhibitor, as a first-line therapy due to its superiority in phase III trials. Although patients enjoy durable responses to alectinib, they eventually develop resistance. Here we describe four cases of primary resistance to alectinib in which the patients show little to no response to alectinib when administered as first or second-line therapy. In order to investigate primary resistance to alectinib, tissue was obtained during re-biopsy and subjected to routine clinical genetic analyses including gene fusion detection and genetic mutation analysis using the Archer FusionPlex and VariantPlex assays, respectively. Concurrently, at the time of biopsy, additional fresh tissue was procured for cell line derivation. The primary cell line was then used to assess ALK and other inhibitors’ potency by cell viability assays. Targeted analysis of signaling pathways was performed in the cell lines via western blot analysis and prox..... READ ARTICLE

Journal of Thoracic Oncology DOI:10.1016/j.jtho.2019.08.1160

Authors: A. Le, L. Tyler, K. Davies, K. Kondo, J. Pacheco, D. Merrick, D. Aisner, D.R. Camidge, R. Doebele